相关论文: Molecular states observed in a single pair of stro…

We study electronic configurations in a single pair of vertically coupled self-assembled InAs quantum dots, holding just a few electrons. By comparing the experimental data of non-linear single-electron transport spectra in a magnetic field…

A quantum dot fabricated by scanning probe oxidation lithography on a p-type, C-doped GaAs/AlGaAs heterostructure is investigated by low temperature electrical conductance measurements. Clear Coulomb blockade oscillations are observed and…

Sequential single-electron charging is observed in InAs Self-Assembled Quantum Dots using capacitance spectroscopy. In this system, the Coulomb energy is smaller than the inter-level energy spacings due to the quantum confinement and both…

The many-particle ground state and excitations of self-assembled InAs quantum dots are investigated using far-infrared (FIR) and capacitance spectroscopy. The contributions of quantization and charging energies to the $n$--electron energy…

Using far-infrared spectroscopy, we investigate the excitations of self-organized InAs quantum dots as a function of the electron number per dot, 1<n<6, which is monitored in situ by capacitance spectroscopy. Whereas the well-known two-mode…

Two tunnel-coupled few-electron quantum dots were fabricated in a GaAs/AlGaAs quantum well. The absolute number of electrons in each dot could be determined from finite bias Coulomb blockade measurements and gate voltage scans of the dots,…

We use photoluminescence spectroscopy to investigate the ground state of single self-assembled InGaAs lateral quantum dot molecules. We apply a voltage along the growth direction that allows us to control the total charge occupancy of the…

We study the electronic coupling between two vertically stacked InAs quantum dots, which are embedded in the center of a n-i-n structure. We use a micro-photoluminescence setup to optically isolate a single quantum dot pair and measure the…

We propose and demonstrate experimentally a novel design of single-electron quantum dots. The structure consists of a narrow band gap quantum well that can undergo a transition from the hole accumulation regime to the electron inversion…

The transport spectrum of a strongly tunnel-coupled one-electron double quantum dot electrostatically defined in a GaAs/AlGaAs heterostructure is studied. At finite source-drain-voltage we demonstrate the unambiguous identification of the…

We report on high-resolution photoluminescence (PL) spectroscopic and microscopic study of laterally coupled InAs/GaAs self-assembled quantum dots by using a low-temperature near-field scanning optical microscope. We have observed slightly…

We have studied theoretically the type-II GaAsSb capped InAs quantum dots for two structures differing in the composition of the capping layer, being either (i) constant or (ii) with Sb accumulation above the apex of the dot. We have found…

We show that a diatomic dot molecule made of two identical, vertically stacked, strained InAs/GaAs self-assembled dots exhibits an asymmetry in its single-particle and may-particle wavefunctions. The single-particle wave function is…

Atomistic electronic structure calculations are performed to study the coherent inter-dot couplings of the electronic states in a single InGaAs quantum dot molecule. The experimentally observed excitonic spectrum [12] is quantitatively…

We report on a combined photoluminescence imaging and atomic force microscopy study of single, isolated self-assembled InAs quantum dots (density <0.01 um^(-2) capped by a 95 nm GaAs layer, and emitting around 950 nm. By combining optical…

Two strongly coupled quantum dots are theoretically and experimentally investigated. In the conductance measurements of a GaAs based low-dimensional system additional features to the Coulomb blockade have been detected at low temperatures.…

Quasi-static transport measurements are employed to characterize a few electron quantum dot electrostatically defined in a GaAs/AlGaAs heterostructure. The gate geometry allows observations on one and the same electron droplet within a wide…

Electronic states and transport phenomena in semiconductor quantum dots are studied theoretically. Taking account of the electron-electron Coulomb interaction by the exact diagonalization method, the ground state and low-lying excited…

Strong confinement of charges in few electron systems such as in atoms, molecules and quantum dots leads to a spectrum of discrete energy levels that are often shared by several degenerate quantum states. Since the electronic structure is…

We have fabricated quantum dot single electron transistors, based on AlGaAs/GaAs heterojunctions without modulation doping, which exhibit clear and stable Coulomb blockade oscillations. The temperature dependence of the Coulomb blockade…